package main

import "fmt"

func main() {
	ages := map[string]int{
		"allen": 20,
		"luffy": 19,
		"zoro":  20,
		"sanji": 20,
	}
	fmt.Printf("allen: %d\n", ages["allen"])   // ok
	fmt.Printf("wukong: %d\n", ages["wukong"]) // ok

	for k, v := range ages {
		fmt.Printf("%s: %d\n", k, v)
	}

	delete(ages, "allen")
	fmt.Println()

	for k, v := range ages {
		fmt.Printf("%s: %d\n", k, v)
	}
}
